The strongest intersections of the circular arcs of earthquakes around Alaska and California from 2005 to 2014

• Main Authors: Jhih-Wun Lin, 林致彣
• Other Authors: Hin-Chi Lei
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/yr2jkz

碩士 === 國立中央大學 === 土木工程學系 === 107 === This study attempts to apply the concept of "the strongest intersection of the circular arcs of earthquakes" which currently used in Taiwan to regions in and around California and Alaska. When searching for the earthquake events from the earthquake catalogue, we gradually decrease the magnitude of earthquakes events from 6 or higher until the first intersection of the circular arcs appears and call it "the strongest intersection of the circular arcs of earthquakes". If in one region there are multiple circular arcs at the same time with the same minimum event magnitude, the arcs with the earliest confirming time will be selected to from the intersection. Then, the intersection will be analyzed and we try to find the relation between the intersection and the nearby strong earthquakes happened after the formation of it. At the same time, the study will establish an earthquake catalogue for research. The earthquake catalogue is divided into two regions of Alaska and California. And the selected data for earthquake events are from the first half of 2005 to the second half of 2014. In Alaska we found 19 strongest intersections of the circular arcs of earthquakes, and in California we found 15 strongest intersections of the circular arcs of earthquakes. The circular prediction reigon of strong earthquakes takes the intersection point as the center and 70 km or Lmin/4 as the radius. Here Lmin/4 represents a quarter of the shortest arc length in the two arcs of the intersection. Afterwards, each intersection is regarded as a case to explore how many days required for the subsequent strong earthquakes in the prediction area, and then we carry out the statistics and analysis of all the intersections from the first half of 2005 to the second half of 2014, and then discuss the impact of the strong earthquake. Alaska、California and Taiwan are all belong to the Circum-Pacific Seismic Zone. The Aleutian Islands which located below Alaska belong to volcanic zone and subduction zone, and San Andreas Fault is transform fault crossing California from north to south. The study will explore the application of the strongest intersection of the circular arcs of earthquakes in these two regions.